The vertical cultivation of plants is gaining increasing significance, in particular in the domain of “urban farming”. Since the available horizontal areas are generally very limited, there is an attempt to increase the yield by using planting containers which permit vertical cultivation. In the case of aeroponics plant systems, the plants are thus fixed in dedicated planting openings of the planting container in such a way that their roots grow into the interior of the planting container where they are wetted with an aerosol of a nutrient solution. This aerosol can be produced e.g. with the aid of nebulisation or sprinkler nozzles in the planting container. In the case of a hydroponics plant system, the plants are rooted in an inorganic substrate which serves merely to hold the plants. In this case, the roots are wetted with nutrient solution via the substrate. Both cultivation methods bring about strong root growth which contributes to an acceleration of the ripening process and results in a high yield.
Various devices and planting containers for the vertical cultivation of plants are known from practice, such as tower-like devices comprising a plurality of circumferential planting tubs arranged one above the other, or even planting walls comprising planting openings, arranged in the manner of a grid, in the wall surfaces.
These known devices consist mostly of a plurality of relatively large and bulky individual parts, the transportation and assembly of which are associated with a comparatively large outlay. Accordingly, these devices are designed generally for a specific usage site where they are constructed once and fixedly installed.
U.S. Patent Application Publication No. 2014/0000162 A1 describes a device for the vertical cultivation of plants which are nourished by wetting the roots with an aqueous nutrient solution. This device comprises a plurality of modularly constructed column elements, the walls of which having planting openings formed therein. The column elements are suspended from a frame in a grid-like arrangement next to one another and one behind the other. Furthermore, this device comprises, for each column element, a supply line which is connected to the upper end of the column element and leads into the column interior, a drain line which is connected to the lower end of the column, a collecting vessel for the nutrient solution which is connected both to the supply line and to the drain line, and a central pumping device, by means of which the nutrient solution is pumped from the collecting vessel via the supply lines into the column interior.
The column element described in U.S. Patent Application Publication No. 2014/0000162 A1 is composed of a plurality of similar planting pots. Each planting pot consists of a circular base plate, a cylindrical wall and a tube portion which extends from the centre of the base plate to the upper edge of the planting pot. The planting openings are formed as protrusions in the upper edge region of the cylindrical wall of the individual planting pots. The planting pots of a column element are attached onto one another such that the tube portions form a central tube which extends over the entire height of the column element. Moreover, the lower edge region of the cylindrical wall or the base plate of each planting pot is provided with a circumferential groove which serves as a retainer for the upper edge region of an adjoining planting pot. Through-going holes for drainage are formed in the base plates of the planting pots so that the nutrient solution can run or drip through the entire column element, i.e. from the uppermost planting pot to the lowermost planting pot and as far as into the collecting vessel.
The structural concept described in U.S. Patent Application Publication No. 2014/0000162 A1 allows column elements of different heights to be produced by varying the number of the structurally identical planting pots mounted one on top of the other. In this manner, the known column elements can also be adapted easily to the particular aspects of the respective installation site.
However, the planting pots described in U.S. Patent Application Publication No. 2014/0000162 A1 have a relatively complicated three-dimensional form. The production thereof is correspondingly expensive. Moreover, the individual planting pots occupy a very large volume when being both transported and stored because they cannot be placed together or stacked in a space-saving manner. Re-use of the planting pots as part of another installation is generally not provided because it proves to be problematic to clean said pots after use and disassemble of a column element by reason of the complicated three-dimensional form.